CEN20LA078

Shortly after the pilot took off for a personal cross-country flight, about 300 ft above ground level, the engine lost partial power. The pilot lowered the airplane nose and the engine continued to operate, before losing total power. The pilot activated the electric fuel boost pump and engine power resumed for a few seconds. The pilot executed a forced landing to a grass area on airport property. During the forced landing, the airplane sustained substantial damage to both wings and the fuselage. Postaccident examination of the airplane revealed blue staining on and around the fuel selector valve area, consistent with a degraded valve. The valve failed leak checks during multiple vacuum tests to check external and internal leakage, which were called for in the manufacturer’s service bulletin 106 A and related airworthiness directive (AD) 2008-05-14. No fuel was found in any fuel lines or components from the firewall forward to the engine fuel components, and about 20 gallons of fuel was recovered from the airplane fuel tanks. It is likely the degraded fuel selector valve was leaking air, which resulted in fuel starvation to the engine. Aircraft records showed that the airplane and fuel selector valve were inspected and returned to service 2 days and about 18 flight hours before the accident. Based on the amount of fuel staining on and around the fuel selector valve and air leakage noted during the tests, the valve had likely become degraded before the last inspection. Given the valve’s degraded condition, it should have been tested and repaired or replaced during the last inspection in compliance with AD 2008-05-14.

On February 9, 2020, about 1500 central standard time, a Navion G airplane, N1011M, impacted terrain during a forced landing near Fort Smith, Arkansas. The pilot, and two passengers sustained minor injuries, one passenger sustained serious injuries, and the airplane sustained substantial damage. The airplane was registered to and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, shortly after takeoff about 300 ft above ground level, the engine lost partial power. The pilot lowered the airplane nose and the engine continued to operate. Shortly thereafter, the engine lost total power. The pilot activated the electric fuel boost pump and engine power resumed; however, the engine lost power again within a few seconds. The pilot executed a forced landing to a grass area on airport property. During the forced landing, the airplane impacted terrain and sustained substantial damage to both wings and the fuselage. Postaccident examination of the airplane by a Federal Aviation Administration (FAA) inspector and a mechanic revealed that the fuel selector valve exhibited blue staining on and around the fuel selector valve area. The fuel selector valve was removed for further examination. No fuel was found in any fuel lines or components from the firewall forward to the engine. About 20 gallons of fuel were removed from the airplane fuel tanks during recovery. A review of the aircraft records showed that an annual inspection was completed and airworthiness directive (AD) 2008-05-14, an inspection of the airplane fuel system, was complied with on February 7, 2020, at a total tachometer time of 224.25 hours. The airplane had accumulated 18.2 hours since the inspections. The FAA inspector examined the fuel selector valve and performed vacuum tests on the valve, in accordance with Navion Service Bulletin (SB) No. 106 A, Fuel System - Inspection of the fuel system continued safe operation. Visual examination of the fuel selector valve showed blue staining, consistent with fuel, near the valve stem and inside the airplane were the fuel selector valve was mounted. Multiple vacuum tests, performed to check external and internal leakage, failed the required leak checks per the SB. The AD referred directly to the SB and stated that the fuel selector valve should be repaired or replaced if it failed the tests.